package teste;

/*
 * @(#)ExtraStorageMergeSortAlgorithm.java  1.0 97/01/09 Jack Snoeyink
 *
 * Copyright (c) 1995 University of British Columbia
 *
 * Permission to use, copy, modify, and distribute this software
 * and its documentation for NON-COMMERCIAL purposes and without
 * fee is hereby granted provided that this copyright notice
 * appears in all copies. Please refer to the file "copyright.html"
 * for further important copyright and licensing information.
 *
 * UBC MAKES NO REPRESENTATIONS OR WARRANTIES ABOUT THE SUITABILITY OF
 * THE SOFTWARE, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
 * TO THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
 * PARTICULAR PURPOSE, OR NON-INFRINGEMENT. UBC SHALL NOT BE LIABLE FOR
 * ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR
 * DISTRIBUTING THIS SOFTWARE OR ITS DERIVATIVES.
 */

/**
 * A merge sort demonstration algorithm using extra space SortAlgorithm.java,
 * Thu Oct 27 10:32:35 1994
 * 
 * @author Jack Snoeyink@cs.ubc.ca
 * @version 1.0, 09 Jan 97
 */
public class ExtraStorageMergeSortAlgorithm extends SortAlgorithm {
	private void sort(int a[], int lo, int hi, int scratch[]) throws Exception {
		if (lo >= hi) {
			return; /* a[lo] is sorted already */
		}

		int mid = (lo + hi) / 2;
		sort(a, lo, mid, scratch); /* Sort sublist a[lo..mid] */
		sort(a, mid + 1, hi, scratch); /* Sort sublist a[mid+1..hi] */

		int k, t_lo = lo, t_hi = mid + 1;
		for (k = lo; k <= hi; k++)
			/* Merge sorted sublists */
			if ((t_lo <= mid) && ((t_hi > hi) || (a[t_lo] < a[t_hi]))) {
				scratch[k] = a[t_lo++];

			} else {
				scratch[k] = a[t_hi++];

			}

		for (k = lo; k <= hi; k++) {
			a[k] = scratch[k]; /* Copy back to a */

		}
	}

	public void sort(int a[]) throws Exception {
		int scratch[] = new int[a.length];
		sort(a, 0, a.length - 1, scratch);
	}
}
